Reinforced concrete sidewalk.



PATENTED MAR. 10, 1908.

P. J. MILLER. REINFORCED CONCRETE SIDEWALK.

APPLICATION FILED NOV. 16. 1907.

INVENTOR WITNESSESZ FRANCIS J. MILLER, OF DETROIT, MICHIGAN.

REINFORCED CONCRETE SIDEW ALK.

Specification of Letters Patent.

Patented March 10, 1908.

Application filed November 16, 1907. Serial No. 402,434.

T c all whom it may concern:

Be it known that I, FRANCIS J. MILLER, a

citizen of the United States of America, re-

siding-at Detroit, in the county of Wayne and t tain new and useful Improvements in Reinforced Concrete Sidewalks, of which the following is a specification, reference being had therein .to the accompanying drawings.

In constructing cement or concrete walks in the usual manner, a bed is formed by digging out the surface clay, loam or acked dirt for the width of the walk, and filing in with sand, gravel or like suitable material, on which the cement or concrete is directly applied and molded in place. The-trench thus filled with earth porous in comparison with the surrounding dirt,.f.orms a natural drain which takes up water running off the edges of the walk and from the adjacent surface. When this freezes, an upheaval and fracture of the cement or concrete coating is inevitable owing to the intimate contact of the latter with the bed surface.

This invention relates to a reinforced concrete or cement walk construction whereb the difficulties above mentioned are obviate and certain other advantages in economy and distribution of material are obtained.

The invention consists in the matters hereinafter set forth, and more particularly pointed out in the appended claims.

Referring to the'drawings, Figure l is a plan view partially brokenaway of a section of sidewalk embodying features of the invention. Fig.2 is a view in section of the walk. Fig. 3 is'a view of the bottom of a slab. Fig. 4 is a view in detail of a slab joint.

As herein illustrated, the sidewalk consists of a suitable bed 1 of gravel, sand, cinders or like material which may be readily leveled to grade,-on which are a series of rectangular slabs. The latter each consists of a thin sheet 2 of'concrete or like cementitious material having a flat or slightly crowned face 3 and flat underside, 4, with dependent marginal flanges 5 connected by centrally disposed cross ribs 6 all integrally united or molded in a single piece.

A metal strip or rod, preferabl cylindrical, bent on itself with its ends we ded to form a frame7, is embedded in the lower portion of the flanges 5, and cross rods 8 whose ends 9 are attached to the frame 7, are inclosed in the lower part of the cross-ribs. A

ate of Michigan, have invented cerseries of parallel spaced wires 10 crossed by aset of separated wires llto which they are preferably joined at their intersections, as by soldering, welding or wrapping, are embedded in the sheet 2 and the end portions 12 of both sets are bent and extended down the flanges, and are preferably attached at their ends to the frame 7. The adjacent margins of the slabs are provided near their tops with interlocking tongues and grooves 13, and below the grooves are slight] cut away to present beveled faces 14, so tiat if the slabs expand longitudinally, they may uptilt or lift slightly without being forced apart at the upper edges. j

The slabs are formed in any suitable mold and then placed on the leveled bed which need not extend to any de th below the flanges. The sand is readi y worked up under each slab into the pockets between the flan es and ribs, the (liVlSlUIlS formed by the ribs eing sufficiently narrow so that the ballast is easily tam ed into them, the width of the ordinary wal precluding such action if the slab were plain. The l'lbS and flan es retain the sand against displacement, and it may or may not form a bearing for the body of the slab, as the dependent members giveam le footing.

ne advantage is the economic distribution of the material which is amply reinforced to prevent fracture. Another feature is the construction of the joints which allow longitudinal expansion without the lifting of.

the slab margins by each other.

The chief advantage is the prevention by the dependent flanges of the entrance of reat distance below the flanges, and the atter act as retaining walls to keep the upper part, which prevents-sidewise movement of the slabs, from working out.

What I claim as my invention is l. A sidewalk comprising a bed of ballast and a series of slabs thereon each consisting of a single rectangular sheet of the full width of the walk, with depending marginal flanges connected at their centers by a pair of intersecting cross-ribs, all molded integrally of cementitious material, a one piece rectangular metal frame embedded in the flanges and cross-rods embedded in the ribs connected at their intersection with each other and at their extremities with the frame, and asquare mesh network of wire embedded in the body of the slab above the lane of the frame with the end portions of tlie wires extending down in the flanges to the frames, the upper portions of the contiguous margins of the slabs being tongued and grooved together and the lower portions bemg slightly beveled inwardly.

2. In a sidewalk, the combination with a bed of ballast of a series of slabs resting thereon interlocked at their margins, each slab comprising a rectangular metal one I piece rim connected by a square mesh inverted basket work of wire and by a pair of intersecting cross wires, all inclosed in an embedment of cementitious material presenting a smooth upper face and a recessed underside adapted to retain the ballast, the transverse mating margins being tongued and grooved near their upper portions and bein slightly beveled inwardly below the inter ocking portions.

In testimony whereof I aflix in presenceof two witnesses.

FRANCIS J. MILLER.

my signature Witnesses C. R. STIOKNEY, Or'ro F. BARTHEL. 

